Furnace



Ap 1 1933. J. M. TAGGART FURNACE e Sheets-Shet 1 Original Filed March 6. 1926 April 11, 1933. 4 J, T A T v 1,903,521

FURNACE Original Filed March 6, 1926 6 Sheets-Sheet 2 VENTOR 97L. /a. B Y j 2 HM A TTOR/VE Y April 11, 1933. J, TAGGART 1,903,521

FURNACE- Original Filed March 6, 1926 6 Sheets-Sheet 3 Fi5TT13 April 11, 1933. J TAGGART 1,903,521

FURNACE.

Original Filed March 6, 1926 6 Sheets-Sheet 4 J. M. TAGGART I FURNACE April 11, 1933.

Original Filed March 6. 1926 6 Sheets-Sheet 5 L A n J 9 0 Q 3 u m n. 0 Z? [N 1 5A" TOR 9h. Wv' A TTURNE )3 April 11 1933. J TAGGART 1,903,521

I FURNACE Original Filed Marbh 6, 1926 6 Sheets-Sheet 6 Fig 5 if I I PNVENTOR g 921' a B) 4 %J A TTORNE V5 Patented Apr. 11, 1933 UNITED STATES JAMES M. TAG-GARE, 01' PORT. WASHINGTON, NEW YORK ruanacn Application filed Inch" 6, 1928,. Serial No. 92,675. Renewed June 23, 1982.

My presentinvention relates to furnaces,

and particularly to means, including superheaters, for cooling the walls of furnaces and, H at the same time, effectively utilizing the heat taken from such walls, and will be best understood from the following description and the annexed drawings, in which Fig. '1

is a vertical longitudinal section of an illustrative form of steam boiler and its furnace embodying my invention; Fig. 2 is'a section on the line 22 of Fig. 1; Flg. 3 is a section on the line 3-3 of Fig.1; Fig. 4 is a;

view similar to Fig. 1, but showing a modiseetion on the line 6-6 of Fig. 4.

Like reference characters indicate like partsin the several views.

In the drawings for purposes of illustration of an embodiment of my invention, I have shown a known. form of a horizontal water tube boiler withlongitudinal steam and water drums, in which the tubes 10 are connected to uptake headers 11 and down take headers 12 which, in turn, are connected to upper steam and water drums 13, the bank of tubes 10 being provided with bafiles of a known form.

Referring now to the embodiment shown in Figs. 1, 2 and 3, the boiler is provided with a furnace chamber. which is substantially rectangular in cross-section and with substantially vertical walls.

stoker 14 is shown located at the bottom of the furnace chamber. Preferably, each of the walls of the furnace chamber is provided 'with a roir'v of horizontally disposed tubes. In the side walls, the set of tubes 15 are con- 6 nected at their ends to vertically disposed headers 16 and 17. The set of tubes 15' are connected between the vertical headers 16' and 17. The horizontal tubes 18 in the front wall are also connected to the headers 16 and 16', and the tubes 18' in the rear wall are con- .nected to the headers 17 and 17 The steam spaces of the drums 13 are connected through a pipe 19 and a branch 20 with the header 16, preferably at a point remote from either end thereof, and the header 17 is connected through a branch 21- to a sufication of my invention; Fig. 5 is a section on the line 5-5 of Fig. 4,.and Fig. 6is a A chain grateperheater steam outlet 22. Steam from the drums 13 flows through the pipes 19 and 20 into the header 16. This steam is distributed by the header 16 to the several tubes 15 and also to the tubes 18. The steam flowing through .tubes 15 enters the rear header 17 by which it is distributed to the tubes 18', through which it flows to the header 17 and from thence to the superheated steam outlet 22. Another portion of the steam in header 16 flows through the tubes 18 to the other header 16 and from there through the tubes 15' to theheader 17 and the branch 21 and superheated steamoutlet 22. In this manner, the steam flows through the tubes which surround the combustion chamber and this not only cools the walls of the furnace chamber, but superheats the steam in an eflicient manner and one which is more nearly independent of the rating at which the boiler is operating than would be the case if the superheater were located in the usual position above the boiler. It will be understood that. the-tubes 15, 15, 18 and 18' are preferably sloped in the direction of the steam flow therein, so that any water carried in with the saturatedsteam from thedrums 13 will flow along with the steam until it itself is converted into steam. I i In the preferred formshown, the tubes 15, 15', 18 and 18 are enclosed in tile, but it will be understood that, if desired, these tubes may be exposed on the inner faces of the furnace walls and that, when in the appended claims I describe the tubes as being in the walls, it'will be understood that, unless otherwise limited, this 'expression includes not only the illustrated arrangement in which the tubes are positioned between the inner and the outer faces of the walls, but also arrangements in which the tubes are either against the inner face of the wallor against the outer face of the wall.

As shown in 1, an opening 23 in the furnace wall may be framed in headers 24, 24, which, in turn, are connected by short tubes 25 above and below the opening, the tubes 15 entering these headers 24, so that 10 the flow of steam through the tubes along this portion of the wall is not interfered with by such an opening.

In certain forms of furnaces, it is desirable to have the furnace space restricted above the fuel feeding apparatus and then expanded and, as a means for accomplishing this, I have omitted, in the form shown in Fig. 1, the horizontal'tubes 18 and 18 over a portion of the front and the rear walls, respectively, of the furnace chamber and have provided in the front wall, an upper horizontal header 26 and a lower horizontal header 27 and in the rear wall, an upper horizontal header 28 and a lower horizontal header 29. A row of tubes 30 have their ends connected respectively to the headers 26 and 27 and have their body portions bent inward to form a reversed arch, as shown best in Fig. 1, the tubes 30 preferably being surrounded by tile in the same manner as shown for the tubes 15 and 18. Similarly at the rear of the furnace, a row of tubes 31 have theirends entered respectively into headers 28 and 29 and with their body portions forming a reversed arch, the tubes 31 also being covered with protecting tile. If desired, combustion air pipes 32 may be provided to supply jets of combustion air between the arches formed by the tubes 30 and 31. w

The upper header 26 is connected to the saturated steam supply pipe 19 by a branch 33 and the lower header 27 is nippled at one end to the vertical header 16. Similarly the lower header 29 is nippled at'one end to the vertical header 17 and the upper header 28 is connected through the branch 34 to the. su-

perheated steam outlet 22.

With the arrangement described, it will I be obvious that the saturated steam from the branch 33 will enter the header 26, flow down through the tubes 30 to the header 27 and from there will flow into the header 16, which, in turn, will supply the steam to the tubes 15'. Similarly steam from the header 17 will flow into the header 29 and then upward through the tubes 31 to the header- 28 and from thence to the superheated steam outlet. With this arrangement, the arches are not only kept cool, but the heat therefrom .superheats the steam passing through the tubes.

In the arrangement shown in Figs. 4, 5 and 6, each of the side walls is provided with a row of horizontally disposed tubes 35 connected to vertical front headers 36 and rear headers 37, these tubes preferably being surrounded by tile, as heretofore described.

In the front wall ofthe furnace is an upper horizontal header 38 and a lower horizontal header 39 connected by a row of tubes 40 having a portion thereof bent outwardly to form a reversed arch and the remainder extending vertically, as best shown in Fig. 4. In the rear wall of the furnace is an upper header Y41 and a lower header 42 connected by a row of tubes 43, also bent to form a reversed arch over the stoker 14 and with portions of the tubes 43 vertically disposed. A saturated steam pipe 44-connects the steam spaces of the drums 13 with the middle portion of the header 38 and the header 39 is nippled at each end to one of the vertical headers 36. Similarly the lower header 42 is nippled at each end to one of the vertical headers 37 and the upper header 41 has a superheated steam outlet 45 connected at the middle portion thereof.

In the arrangement just described, the saturated steam enters the header 38, flows through the tubes 40 into the header 39 and from there it divides, some of it flowing into one and some of it into the other of the headers 36, from which it flows through the tubes 35 to the headers 37 ,from which, in turn, it

stood that such arrangement may be provided'for some of the walls only, the other walls, in such case, having any other type of construction.

It will also be understood that the cooling vapor may be supplied to the cooling tubes from any source and that my cooling arrangement may be used in furnaces other than those supplying hot gases to boilers and particularly to the boiler which is the source of the cooling steam.

By my arrangement, difliculties experienced with water-cooled walls'are obviated.

In such water-cooled walls, the tubes are liable to become clogged from scale and the like deposited from the water and, at low loads particularly, corrosion'of the cooling tubes may occur because of the sluggish circulation of the water. as the cooling medium, there are practically no impurities carried into the tubes, so that the possibility of clogging and corrosion is negligible. By maintaining a relatively small pressure drop through the tubes, high steam velocities occur and this will provide suflicient heat absorption to cool the walls. Furthermore, since differences in static head,

'which occur when water is used as the cooling medium, are not found when steam is used as the cooling medium, the steam may be caused to flow downward in a set of tubes, if desired, without causing difficulties in circulation or distribution of the steam between the several tubes of such a set.

, I claim: I p

1. A furnace having a combustion chamber with a substantially rectangular cross When, steam is used section,-horizontally disposed tubes in the side walls of the furnace, vertically disposed headers connected to the ends of said horizontally disposed tubes, vertically disposed bent tubes at the front and back of the furnace with their ends in the furnace wall and with at least a portion of the body portions of said benttubes extending into the furnace space, a steam inlet and a steam outlet connected to all said tubes, and a source of steam supply connected to said inlet.

2. A furnace having a combustion chamber with a substantially rectangular cross section, horizontally disposed tubes in the side walls of the furnace, vertically disposed headers connected to the ends of said horizontally disposed tubes, horizontal upper and lower headers outside of the furnace faces of the front and rear furnace walls with each of the lower horizontal headers connected at each end to one of said vertical headers, vertically disposed tubes connecting said upper and lower horizontal headers, and means for passing a fluid through said vertically disposed tubes.

3. A furnace having a combustion chamber with a substantially rectangular cross section, horizontally disposed tubes in the I side walls of the furnace, vertically disposed 3o headers connected to the ends of said horizontally disposed tubes, horizontal upper and lower headers outside of the furnace faces of the front and rear furnace walls with each of the lower horizontal headers connected at each end to one of said vertical headers,

vertically disposed bent tubes connecting said upper and lower horizontal headers with at least a portion of the body portions of said bent tubes extendin 4 into the furnace space, and means for passing a fluid through said vertically disposed tubes.

4. A. furnace chamber substantially rectangular in cross section, a vertical header at each corner of the furnace, horizontally disposed tubes in the walls of the furnace and connecting said headers, an inlet pipe connected with one of said headers at a point remote from either end of the header, an outlet pipe connected to another of said headers at a point remote from either end of the header, and a source of steam supply connected-to said inlet.

'5. A furnace having a combustion chamber with a substantially rectangular cross 66 section, horizontally disposed tubes in the side walls of the furnace, vertically disposed headers connected to the ends of said horizontally disposed tubes, horizontal upper and lower headers in the front and rear furnace walls with each of the lower horizontal headers connected at each end to one of said vertical headers, vertically disposed bent tubes connecting said upper and lower-horizontal headers with at least a portion of the body section, horizontally disposed tubes, in the side walls of the furnace, vertically disposed headers connected to the ends of said horizontally disposed tubes, horizontal upper and lower headers outside the furnace faces of the front and rear furnace walls with each of the lower horizontal headers connected to one of said vertical headers, vertically disposed bent tubes connecting said upper and lower horizontal headers with at least a portion of the body portions of said bent tubes extending into the furnace space, and means for passing a fluid through said vertically disposed tubes.

7. A furnace having a combustion chamber with a substantially rectangular cross section, horizontally disposed tubes in the side walls of the furnace, vertically disposed headers connected to the vends of said horizontally disposed tubes, horizontal upper and lower headers in the front and rear furnace walls with each of the lower horizontal headers connected to one of said vertical headers, vertically disposed bent tubes connecting said upper and lower horizontal-headers with at least a portion of the body portions of said bent tubes extending into the furnace space, asteam inlet connected to the upper one of said horizontal headers in one of said walls, a steam outlet connected to the upper one of said horizontal headers in the other of said said tubes and extending substantially throughout the lengths of the arches.

JAMES M. TAGGART.

' portions of said bent tubes extending into 

